Question

i have two view controllers, FirstViewController and DetailViewController, switch back and forth.

in didSelectRowAtIndexPath method —> updateRowNumber:indexPath.row, i pass the selected row number to DetailViewController.

the first time, it worked, FirstViewController can pass the selected row to DetailedViewController, after switch back and forth, it still get the last selected row.

anyone knows what i missed?

#import "FirstViewController.h"
#import "AppDelegate.h"
#import "DetailViewController.h"
#import "PartyListCustomViewCell.h"

@interface FirstViewController ()

@end

@implementation FirstViewController

@synthesize dvController;  // it is a DetailViewController

- (void) viewDidLoad
{
contentArray = [[NSArray arrayWithObjects:@"heyun", @"wushi", @"ios", nil]retain];

[super viewDidLoad];

}


- (id)initWithNibName:(NSString *)nibNameOrNil bundle:(NSBundle *)nibBundleOrNil
{
    self = [super initWithNibName:nibNameOrNil bundle:nibBundleOrNil];
    if (self) {
        // Custom initialization
    }
    return self;
}

- (void) dealloc
{
    [dvController release];
    [super dealloc];
}

- (void)didReceiveMemoryWarning
{
    [super didReceiveMemoryWarning];
    // Dispose of any resources that can be recreated.
}

- (void)viewWillAppear:(BOOL)animated
{
    [super viewWillAppear: animated];    
}

- (void)viewDidAppear:(BOOL)animated
{
    [super viewDidAppear: animated];
}

- (void)viewWillDisappear:(BOOL)animated
{
    [super viewWillDisappear: animated];
}

- (void)viewDisDisappear:(BOOL)animated
{
    [super viewDidDisappear: animated];
}

- (NSInteger)numberOfSectionsInTableView: (UITableView *)tableView
{
    return 1;
}

- (NSInteger)tableView:(UITableView *)tableView numberOfRowsInSection:(NSInteger)section
{

    return [contentArray count];
}

// custom row height
- (CGFloat)tableView:(UITableView *)tableView heightForRowAtIndexPath:(NSIndexPath *)indexPath
{
    // dynamic with whether the cell has the party image or not..
    return 160;
}

// Customize the appearance of table view cells
- (UITableViewCell *) tableView:(UITableView *)tableView cellForRowAtIndexPath:        (NSIndexPath *)indexPath
{
    static NSString *CellIdentifier = @"PartyListCustomCell";

    PartyListCustomViewCell *plcc = [tableView     dequeueReusableCellWithIdentifier:CellIdentifier];

    if(plcc == nil)
    {
        plcc = [[[PartyListCustomViewCell alloc] initWithStyle:UITableViewCellStyleDefault reuseIdentifier:CellIdentifier] autorelease];
    }


    // set up custom cell
    plcc.partyTitle.text = @"partyTitle";


    return plcc;

}

- (void) tableView:(UITableView *)tableView didSelectRowAtIndexPath:(NSIndexPath *)indexPath
{

    if (dvController == nil)
    {
        DetailViewController *aController = [[DetailViewController alloc] initWithNibName:@"DetailViewController" bundle:nil];

        self.dvController = aController;

        [aController release];
    }   

    [dvController updateRowNumber:indexPath.row];
    [[self navigationController] pushViewController:dvController animated:YES];

}

@end



#import "DetailViewController.h"


@interface DetailViewController ()

@end

@implementation DetailViewController

@synthesize rowNumber;

- (id)initWithNibName:(NSString *)nibNameOrNil bundle:(NSBundle *)nibBundleOrNil
{
    self = [super initWithNibName:nibNameOrNil bundle:nibBundleOrNil];
    if (self) 
    {
        // Custom initialization
    }
    return self;
}

- (void) updateRowNumber: (int) theindex
{

    rowNumber = theindex + 1;    
}

- (void)dealloc
{

    [super dealloc];
}

- (void)viewDidLoad
{

    UILabel *label1 = [[UILabel alloc]initWithFrame:CGRectMake(50.0, 20.0, 200.0, 50.0)];

    label1.text = [NSString stringWithFormat:@"row %i was clicked ", rowNumber];

    [self.view addSubview: label1];

    [super viewDidLoad];
    [label1 release];
    // Do any additional setup after loading the view from its nib.
}

- (void)viewDidUnload
{
    [super viewDidUnload];
    // Do any additional setup after loading the view from its nib.
}

- (void)viewWillAppear:(BOOL)animated
{   
    [super viewWillAppear: animated];
}

- (void)viewDidAppear:(BOOL)animated
{
    [super viewDidAppear: animated];
}

- (void)didReceiveMemoryWarning
{
    [super didReceiveMemoryWarning];
    // Dispose of any resources that can be recreated.
}

@end

Answer 1

First off, if “dvController” is a property change the “dvController” references in your “didSelectRowAtIndexPath” method to “self.dvController“.

Secondly, in your “DetailViewController” object, when the “updateRowNumber” method fires… it doesn’t look like you do anything else (i.e. updating the views or whatever) after that, aside from updating the internal row number.